using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Windows.ApplicationModel.Contacts;
 
namespace Microsoft.Maui.ApplicationModel.Communication
{
	class ContactsImplementation : IContacts
	{
		public async Task<Contact> PickContactAsync()
		{
			var contactPicker = new ContactPicker();
 
			var hwnd = WindowStateManager.Default.GetActiveWindowHandle(true);
			WinRT.Interop.InitializeWithWindow.Initialize(contactPicker, hwnd);
 
			var contactSelected = await contactPicker.PickContactAsync();
			return ConvertContact(contactSelected);
		}
 
		public async Task<IEnumerable<Contact>> GetAllAsync(CancellationToken cancellationToken)
		{
			var contactStore = await ContactManager.RequestStoreAsync()
				.AsTask(cancellationToken).ConfigureAwait(false);
			if (contactStore == null)
				throw new PermissionException("Permission to access the contacts was denied.");
 
			var contacts = await contactStore.FindContactsAsync()
				.AsTask(cancellationToken).ConfigureAwait(false);
			if (contacts == null || contacts.Count == 0)
				return Array.Empty<Contact>();
 
			return GetEnumerable();
 
			IEnumerable<Contact> GetEnumerable()
			{
				foreach (var item in contacts)
				{
					yield return ConvertContact(item);
				}
			}
		}
 
		internal static Contact ConvertContact(global::Windows.ApplicationModel.Contacts.Contact contact)
		{
			if (contact == null)
				return default;
 
			var phones = contact.Phones?.Select(
				item => new ContactPhone(item?.Number))?.ToList();
			var emails = contact.Emails?.Select(
				item => new ContactEmail(item?.Address))?.ToList();
 
			return new Contact(
				contact.Id,
				contact.HonorificNamePrefix,
				contact.FirstName,
				contact.MiddleName,
				contact.LastName,
				contact.HonorificNameSuffix,
				phones,
				emails,
				contact.DisplayName);
		}
	}
}